Generally, in electronic apparatus which are utilized as so-called mobile terminal apparatus such as portable telephone sets and personal digital assistants, a liquid crystal display panel, an organic EL (electroluminescence) panel or the like is used as a display apparatus. However, one of characteristics of mobile terminal apparatus is that they can be used under various environments (for example, outdoors). Accordingly, it is necessary for a display apparatus used in a mobile terminal apparatus to be capable of display a good image under various environments.
It is a possible idea to use, in order to be used under various environments, a display apparatus configured such that the brightness of a backlight for liquid crystal elements can be adjusted in response to a result of detection of the external light intensity (refer to, for example, Japanese Patent Laid-Open No. Hei or Japanese Patent Laid-Open No. 2000-294026). This is because the display apparatus of the type described can increase the brightness of the backlight under an environment in which the external light intensity is high such as outdoors, and suppress the brightness of the backlight under an environment wherein the external light intensity is low such as indoors.